Switch



Patented Aug. 7,1945

assrsss swrrcn John 0. Moorhead, Attleboro, Mass.,

Metals and Controls Corporation,

assignor to Attleboro,

Mass., a corporation of Massachusetts Application December 1s, 1943,serial'No. 514,157,

(ci. 20a-s) 8 Claims.

This invention relates to switches, and with regard to certain morespecific features, to multipole, snap-acting switches.

Among the several objects of the invention may be noted the` provisionof a multi-pole, snap-acting switch of simple organization which may beeconomically fabricated and easily assembled; the provision of a switchof the class described which, by a very simple structure, obtains,equalized snap-action; and the provision of a switch of this class inwhich creep action of the snapacting .element does not translate intocreep action in certain switch operations. Other objects will be in partobvious and-in part pointed out hereinafter.

The invention accordingly comprises the elements and combinations ofelements, features of construction, "and will be exemplified in thestructures hereinafter described, and the scope of the application ofwhich will be indicated in the following claims.

In vthe accompanying drawing, in which is illustrated one of variouspossible embodiments of the invention, i

Fig. l is a top plan view of the switch about full Size;

Fig. 2 is e, front elevation of Fig. 1;

Fig. 3 is a bottom plan view of Fig. '2;

Fig. 4 is an enlarged horizontal section taken on line 4-4 of Fig. 2;

arrangements of parts which l formed four holes 45.

Fig. 5 is an enlarged vertical section taken on line 5-5 of Fig. 2; and,

Fig. 6 is a vertical section taken online 6-6 of Fig. 5.

Referring to the drawing, numeral I indicates a molded insulatingbottom-forming base. This base I forms the foundation for a sub-assemblywhich comprises a row of line terminals 3, to which are riveted springcontact arms 5. The latter bias upward. At the ends of the spring arms 5are contacts 1. Upward bias of the arms normally forces the upper facesof the contacts 1 against upper contacts 3 on rigid conductingextensions Il. The extensions II are riveted to a second row of lineterminals I3. The lower faces of the contacts 1. are adapted to engagelwith contacts I5, mounted on rigid extensions I1, the latter beingriveted to a third row of line terminalsl I3. From the above it will beseen that the spring arms 5 normally bias up to close parallel circuitsbetween the respective contacts of the rows of line terminals 3 and I3.When the arms 5 are pushed down, they substantially simultaneously closeparallel circuits through respective pairs of the line terminals 3 andI9.

Each line terminal is made as is the one shown at the right in' sectionin Fig. 5, being tapped and provided with a terminal screw 2I. Eachscrew is in a molded socket 23 having a side outlet for the insertion oflead-in wires (Figs. 3 and 5).

Above the base l is a separatesub-base member 25 made up of moldedinsulating material. This ishollowed as shown Aat 21 to surround theswitch operating parts on the top of the base I. The sub-base 25 alsohas an integral median partition wall 28 located between a central pairof' switch elements, the latter being indexed in general by. numeralslbase I also has integral separating walls 39 which separate the pairs ofswitch Vunits which are indexed in general as 3l, 33 and 35, 31 in Fig.6. Thus each switch is in a separate compartment between the bases I and25.v Furthermore, the central wall29 of the vsub-base 25 is providedwith holes for holding screws 4I which are threaded into the portion ofthe base I just below the wall 29 (Fig. 5). These screws hold t0- getherthe two bases.

Above the vertical wall 23, the member 25 is formed as a horizontal wall43 in which are These are located along a line at right angles totheseparating wall 29 and directly above the spring arms 5. They formvertical guides for short cylindric insulating and operating pins 41,the latter having rounded ends. These pins slide in the guides 45 andrest upon the arm 5. They are light in weight being also molded frominsulating material. They protrude slightly above the upper surface ofthe horizontal wall 43. 4

On the upper ends of the pins 41 rests an equalizing and operating bar49. The support is a loose .rocking one and the ends of the bar areroundedas indicated at 5I, loosely to engage notches 53 in the peripheryof a disc-shaped recess 55. Recess 55 is formed above the horizontalwall 43 and in the sub-base 25. In this recess 55 is an angular shoulder51 which supports van over-centering, snap-acting spring disc 59. Thenormal stable condition of curvature of the disc is convex upward asshown in Fig. 5.

Enclosing the top of the member 25 is a hat metal cap 5I, held in placeby four screws $3. Centrally this cap 6I has riveted to it a hollowbushing 64 threaded at 85 to receive a nut 51 for attachment purposes topanels and the like. Sliding inside of the bushing 64 is a hollow sleeve69, the upper end of which 1I. The sleeve is prevented from beingdepressed more than a limited extent by means of a snap 33 and 35 inFig. 6. The

forms a push button ring 19 forming an outer shoulder. .At its lower endthe sleeve 99 has an outwardly directed shoulder 15 engaging an inwardlydirected shoulder 11 of the bushing 5l for limiting outward biasedmovement of the sleeve 59.

Within the sleeve 69 is an abutment insert 19 for a compression spring9|. The lower end of the spring 9| engages an abutment 53, the latterhaving a nipple 85 extendingl loosely into an opening 51 of the disc 59.The abutment 53 is hollow as indicated at 9|l the hollow portionproviding some lost motion with respect to an operating abutment pin-93fastened rigidly to the center of the top of the operatingbar 49.

For ease of assembly, the nipple 95 is removable from the opening 51 andthe abutment 19 is removable from and insertable in the sleeve 59. Thespring merely abuts the members 19 and 83.

Operation is as follows, starting with the switch-closed position ofparts showrrin Fig, 5.

Pressure on the button 1| forces the sleeve 59 down into the bushing B4which compresses ythe spring 8|. This applies resilient pressure to thetop of the disc 59. The latter, under load, after slight creep, snaps orovercenters quickly from the upwardly arched position shown to thedownwardly arched position,lin which the pin 93 of bar 49 iscontacted.This drives the equalizing bar 49 down against the four pins 41 whichrespectively'push down the switch arms 5 out of contact with contacts 9and into contact with the contacts I5. When pressure is released uponthe button 1| the disc 59 again snaps up to lthe position shown in Fig.5, thus allowing the arms 5 to reset themselves into their initialupwardly biased positions.

The play or loose connection between the operating pin 93 and the socket9| in member 83 is doubly important.' First, it allows any preliminaryslow-acting creep movement of the disc 59 to occur without transmittingcreep movement to the arms 5. Then, as the disc snaps downwardly itstrikes the pin 93 with more or less of a blow, which suddenly opens allof the contacts practically at once. Second, the play allows completefreedom of the bar 49 to assume an equalizing position on the pins 41.In this connection it will be observed that the spring arms 5gravitationally support the equalizing bar 49 through pins 41.

The slow-acting creep movement of disc 59 at the start of its by makingthe pins 41 of such length that the Pins and bar all have loose fits.The disc 59 is then dropped into place and the cover 6| is applied, thelatter having already had attached to it the bushing and button parts.At the time the cover 5| is applied, the members 69, 19, 83 and spring9| are inserted. The cover 6| is then fastened down withthe screws 53,thus pre-compressing the spring 8|, but not to an extent which will snapdown the disc 59. l

return motion is compensated for` spectively in said guide openings Asmany changes could be made in the above constructions without departingfrom the scope of the invention, it is intended that all mattercontained in the above description or shown in the accompanying drawingshall be interpreted -as illustrative and not in a limiting sense.

a plurality of spring switch arms biased in one direction, operatingpins supported by said arms, an equalizer bar supported by said pins, asnapacting spring disc member cooperating with lost motion with saidequalizer bar and manually operated resilient means for applying a loadthrough said spring member to the disc to snap it in a direction to takeup said lost motion toward said equalizer bar and to drive it againstsaid pins to operate said switch arms.

3. A multi-pole snap-acting switch comprising a plurality of parallelspring switch bars biased in a. certain direction and locatedside-by-side, a. row of operating pins supported by said arms, said rowextending perpendicular to the bar lengths, an equalizer bar supportedby said pins and extending parallel to said row, an operating abutmenton said bar, a snap-acting spring disc member cooperating centrally withlost motion with said abutment oi.' the equalizer bar, and manuallyoperated resilient means for applying a resilient load, said disc tosnap it in a direction to take up said lost motion and to drive saidequalizer bar through said abutment and against said pins to operatesaid switch arms.

4. In a multi-pole snap-acting switch, a switcharm assembly comprising abase, rows of paired line terminals thereon, a plurality of switch armssupported by certain of said terminals, an insulating covering memberattached to said base and covering said switch-arm assembly, said covermember having a shouldered recess, a snapacting spring disc supported insaid recess, guide openings through the cover member extending from saidrecess, sliding pins respectively in said guide openings andrespectively` engaging the switch arms, and an equalizing bar located insaid recess under the disc and engaging said pins and operated by saidspring disc.

5. In a multi-.pole sna -acting switch, a switcharm assembly comprisinga base, rows of paired line terminals thereon, a plurality of switcharms supported by certain of said terminals, contacts carried by certainof the line terminals and .n position to cooperate with said switcharms, an insulating covering member attached to said base and coveringsaid switch arm assembly, said cover member having a shouldered re.cess, a snap-acting spring disc supported in said recess, guide openingsthrough the cover member extending from said recess, sliding pinsrespringv disc, said and resilient pressure means connecting the pushandI having there between a horizontal wail and button and the disc. awall separating other of said switch assemblies 6. A multi-polesnap-acting switch comprising on the main base, the inside one oi saidrecesses a main insulating base, a. plurality of switch asaccommodatingall of the switch assemblies, semblies carried on said base, parallelseparating 5 means for fastening the auxiliary 'oase to the wallsforming part of the base and separating main base through saidseparating wall, a row some of said switch assemblies, an auxiliary baseof openings joining said recesses and extending formed with outside andinside recesses and havperpendicularly to said separating wall, shdinging therebetween a horizontal wall and a wall pins in said openingsrespectively, a snap-acting separating other of said switch assemblieson the spring disc carried in the outside recess and main base, theinside one of said recesses acnormally concave toward said pins and anequalcommodating all of theswitch assemblies, means izer bar in saidoutside recess resting upon said for fastening the auxiliary base to themain base pins, said outside recess being peripherally through itsseparating wall, a row of openings notched to guide the ends of the bar,lost motion joining said recesses and extending perpendicu- Hiengagement means between the disc and said larly to said separatingwall, sliding pins in said equalizing bar, and a cover on said auxiliarybase openings respectively, a snap-acting spring disc enclosing saidoutside recess, a bushing attached carried in the outside recess andnormally conto said cover, sliding operating means in said cave towardsaid pins and an equalizer bar in bushing and a spring between saidsliding opersaid outside recess resting upon said pins, said zo atingmeans and connected tc apply force resiloutside recess beingperipherally notched to guide iently to said disc. the ends of the bar.8. A multi-pole 'snap-acting switch comprising '1. A multile snap-actingswitch comprisa plurality of biased spring switch arms, oper-f ing amain insulating base, a plurality of switch ating pins supported by saidarms, a loosely assemblies carried on said base, parallel separat- 25guided equalizer bar supported by said pins, and ing walls forming partof the base and separata snap-acting spring member cooperating with ingsome of said switch assemblies, an auxillost motion withsaid equalizerbar. iary oase formed with outside and inside recesses JOHN O. MOORHEAD.

